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T-SQL generate merge statement sproc
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-- SEE BELOW for Attribution... I have modified this sproc to incorporate additional data types | |
-- such as datetimeoffset, etc. | |
-- I have used it on MSSQL Server 2008R2 through 2017 | |
CREATE PROC [dbo].[sp_generate_merge] | |
( | |
@table_name varchar(776), -- The table/view for which the MERGE statement will be generated using the existing data | |
@target_table varchar(776) = NULL, -- Use this parameter to specify a different table name into which the data will be inserted/updated/deleted | |
@from nvarchar(max) = NULL, -- Use this parameter to filter the rows based on a filter condition (using WHERE) | |
@include_timestamp bit = 0, -- Specify 1 for this parameter, if you want to include the TIMESTAMP/ROWVERSION column's data in the MERGE statement | |
@debug_mode bit = 0, -- If @debug_mode is set to 1, the SQL statements constructed by this procedure will be printed for later examination | |
@schema varchar(64) = NULL, -- Use this parameter if you are not the owner of the table | |
@ommit_images bit = 0, -- Use this parameter to generate MERGE statement by omitting the 'image' columns | |
@ommit_identity bit = 0, -- Use this parameter to ommit the identity columns | |
@top int = NULL, -- Use this parameter to generate a MERGE statement only for the TOP n rows | |
@cols_to_include varchar(8000) = NULL, -- List of columns to be included in the MERGE statement | |
@cols_to_exclude varchar(8000) = NULL, -- List of columns to be excluded from the MERGE statement | |
@update_only_if_changed bit = 1, -- When 1, only performs an UPDATE operation if an included column in a matched row has changed. | |
@delete_if_not_matched bit = 1, -- When 1, deletes unmatched source rows from target, when 0 source rows will only be used to update existing rows or insert new. | |
@disable_constraints bit = 0, -- When 1, disables foreign key constraints and enables them after the MERGE statement | |
@ommit_computed_cols bit = 0, -- When 1, computed columns will not be included in the MERGE statement | |
@include_use_db bit = 1, -- When 1, includes a USE [DatabaseName] statement at the beginning of the generated batch | |
@results_to_text bit = 0, -- When 1, outputs results to grid/messages window. When 0, outputs MERGE statement in an XML fragment. | |
@include_rowsaffected bit = 1, -- When 1, a section is added to the end of the batch which outputs rows affected by the MERGE | |
@nologo bit = 0, -- When 1, the "About" comment is suppressed from output | |
@batch_separator VARCHAR(50) = 'GO' -- Batch separator to use | |
) | |
AS | |
BEGIN | |
-- exec [sp_generate_merge @schema = 'SCHEMA_NAME', @table_name = 'TABLE_NAME', @update_only_if_changed = 0, @delete_if_not_matched = 0, @batch_separator = '' -- | |
/*********************************************************************************************************** | |
Procedure: sp_generate_merge (Version 0.93) | |
(Adapted by Daniel Nolan for SQL Server 2008/2012) | |
Adapted from: sp_generate_inserts (Build 22) | |
(Copyright © 2002 Narayana Vyas Kondreddi. All rights reserved.) | |
Purpose: To generate a MERGE statement from existing data, which will INSERT/UPDATE/DELETE data based | |
on matching primary key values in the source/target table. | |
The generated statements can be executed to replicate the data in some other location. | |
Typical use cases: | |
* Generate statements for static data tables, store the .SQL file in source control and use | |
it as part of your Dev/Test/Prod deployment. The generated statements are re-runnable, so | |
you can make changes to the file and migrate those changes between environments. | |
* Generate statements from your Production tables and then run those statements in your | |
Dev/Test environments. Schedule this as part of a SQL Job to keep all of your environments | |
in-sync. | |
* Enter test data into your Dev environment, and then generate statements from the Dev | |
tables so that you can always reproduce your test database with valid sample data. | |
Written by: Narayana Vyas Kondreddi | |
http://vyaskn.tripod.com | |
Daniel Nolan | |
http://danere.com | |
@dan3r3 | |
Acknowledgements (sp_generate_merge): | |
Nathan Skerl -- StackOverflow answer that provided a workaround for the output truncation problem | |
http://stackoverflow.com/a/10489767/266882 | |
Bill Gibson -- Blog that detailed the static data table use case; the inspiration for this proc | |
http://blogs.msdn.com/b/ssdt/archive/2012/02/02/including-data-in-an-sql-server-database-project.aspx | |
Bill Graziano -- Blog that provided the groundwork for MERGE statement generation | |
http://weblogs.sqlteam.com/billg/archive/2011/02/15/generate-merge-statements-from-a-table.aspx | |
Acknowledgements (sp_generate_inserts): | |
Divya Kalra -- For beta testing | |
Mark Charsley -- For reporting a problem with scripting uniqueidentifier columns with NULL values | |
Artur Zeygman -- For helping me simplify a bit of code for handling non-dbo owned tables | |
Joris Laperre -- For reporting a regression bug in handling text/ntext columns | |
Tested on: SQL Server 2008 (10.50.1600), SQL Server 2012 (11.0.2100) | |
Date created: January 17th 2001 21:52 GMT | |
Modified: May 1st 2002 19:50 GMT | |
Last Modified: September 27th 2012 10:00 AEDT | |
Email: dan@danere.com, vyaskn@hotmail.com | |
NOTE: This procedure may not work with tables with a large number of columns (> 500). | |
Results can be unpredictable with huge text columns or SQL Server 2000's sql_variant data types | |
IMPORTANT: This procedure has not been extensively tested with international data (Extended characters or Unicode). If needed | |
you might want to convert the datatypes of character variables in this procedure to their respective unicode counterparts | |
like nchar and nvarchar | |
Get Started: Ensure that your SQL client is configured to send results to grid (default SSMS behaviour). | |
This ensures that the generated MERGE statement can be output in full, getting around SSMS's 4000 nchar limit. | |
After running this proc, click the hyperlink within the single row returned to copy the generated MERGE statement. | |
Example 1: To generate a MERGE statement for table 'titles': | |
EXEC sp_generate_merge 'titles' | |
Example 2: To generate a MERGE statement for 'titlesCopy' table from 'titles' table: | |
EXEC sp_generate_merge 'titles', 'titlesCopy' | |
Example 3: To generate a MERGE statement for table 'titles' that will unconditionally UPDATE matching rows | |
(ie. not perform a "has data changed?" check prior to going ahead with an UPDATE): | |
EXEC sp_generate_merge 'titles', @update_only_if_changed = 0 | |
Example 4: To generate a MERGE statement for 'titles' table for only those titles | |
which contain the word 'Computer' in them: | |
NOTE: Do not complicate the FROM or WHERE clause here. It's assumed that you are good with T-SQL if you are using this parameter | |
EXEC sp_generate_merge 'titles', @from = "from titles where title like '%Computer%'" | |
Example 5: To specify that you want to include TIMESTAMP column's data as well in the MERGE statement: | |
(By default TIMESTAMP column's data is not scripted) | |
EXEC sp_generate_merge 'titles', @include_timestamp = 1 | |
Example 6: To print the debug information: | |
EXEC sp_generate_merge 'titles', @debug_mode = 1 | |
Example 7: If the table is in a different schema to the default, use @schema parameter to specify the schema name | |
To use this option, you must have SELECT permissions on that table | |
EXEC sp_generate_merge 'Nickstable', @schema = 'Nick' | |
Example 8: To generate a MERGE statement for the rest of the columns excluding images | |
EXEC sp_generate_merge 'imgtable', @ommit_images = 1 | |
Example 9: To generate a MERGE statement excluding (omitting) IDENTITY columns: | |
(By default IDENTITY columns are included in the MERGE statement) | |
EXEC sp_generate_merge 'mytable', @ommit_identity = 1 | |
Example 10: To generate a MERGE statement for the TOP 10 rows in the table: | |
EXEC sp_generate_merge 'mytable', @top = 10 | |
Example 11: To generate a MERGE statement with only those columns you want: | |
EXEC sp_generate_merge 'titles', @cols_to_include = "'title','title_id','au_id'" | |
Example 12: To generate a MERGE statement by omitting certain columns: | |
EXEC sp_generate_merge 'titles', @cols_to_exclude = "'title','title_id','au_id'" | |
Example 13: To avoid checking the foreign key constraints while loading data with a MERGE statement: | |
EXEC sp_generate_merge 'titles', @disable_constraints = 1 | |
Example 14: To exclude computed columns from the MERGE statement: | |
EXEC sp_generate_merge 'MyTable', @ommit_computed_cols = 1 | |
***********************************************************************************************************/ | |
SET NOCOUNT ON | |
--Making sure user only uses either @cols_to_include or @cols_to_exclude | |
IF ((@cols_to_include IS NOT NULL) AND (@cols_to_exclude IS NOT NULL)) | |
BEGIN | |
RAISERROR('Use either @cols_to_include or @cols_to_exclude. Do not use both the parameters at once',16,1) | |
RETURN -1 --Failure. Reason: Both @cols_to_include and @cols_to_exclude parameters are specified | |
END | |
--Making sure the @cols_to_include and @cols_to_exclude parameters are receiving values in proper format | |
IF ((@cols_to_include IS NOT NULL) AND (PATINDEX('''%''',@cols_to_include) = 0)) | |
BEGIN | |
RAISERROR('Invalid use of @cols_to_include property',16,1) | |
PRINT 'Specify column names surrounded by single quotes and separated by commas' | |
PRINT 'Eg: EXEC sp_generate_merge titles, @cols_to_include = "''title_id'',''title''"' | |
RETURN -1 --Failure. Reason: Invalid use of @cols_to_include property | |
END | |
IF ((@cols_to_exclude IS NOT NULL) AND (PATINDEX('''%''',@cols_to_exclude) = 0)) | |
BEGIN | |
RAISERROR('Invalid use of @cols_to_exclude property',16,1) | |
PRINT 'Specify column names surrounded by single quotes and separated by commas' | |
PRINT 'Eg: EXEC sp_generate_merge titles, @cols_to_exclude = "''title_id'',''title''"' | |
RETURN -1 --Failure. Reason: Invalid use of @cols_to_exclude property | |
END | |
--Checking to see if the database name is specified along wih the table name | |
--Your database context should be local to the table for which you want to generate a MERGE statement | |
--specifying the database name is not allowed | |
IF (PARSENAME(@table_name,3)) IS NOT NULL | |
BEGIN | |
RAISERROR('Do not specify the database name. Be in the required database and just specify the table name.',16,1) | |
RETURN -1 --Failure. Reason: Database name is specified along with the table name, which is not allowed | |
END | |
--Checking for the existence of 'user table' or 'view' | |
--This procedure is not written to work on system tables | |
--To script the data in system tables, just create a view on the system tables and script the view instead | |
IF @schema IS NULL | |
BEGIN | |
IF NOT EXISTS (SELECT 1 FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME = @table_name AND (TABLE_TYPE = 'BASE TABLE' OR TABLE_TYPE = 'VIEW') AND TABLE_SCHEMA = SCHEMA_NAME()) | |
BEGIN | |
RAISERROR('User table or view not found.',16,1) | |
PRINT 'You may see this error if the specified table is not in your default schema (' + SCHEMA_NAME() + '). In that case use @schema parameter to specify the schema name.' | |
PRINT 'Make sure you have SELECT permission on that table or view.' | |
RETURN -1 --Failure. Reason: There is no user table or view with this name | |
END | |
END | |
ELSE | |
BEGIN | |
IF NOT EXISTS (SELECT 1 FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME = @table_name AND (TABLE_TYPE = 'BASE TABLE' OR TABLE_TYPE = 'VIEW') AND TABLE_SCHEMA = @schema) | |
BEGIN | |
RAISERROR('User table or view not found.',16,1) | |
PRINT 'Make sure you have SELECT permission on that table or view.' | |
RETURN -1 --Failure. Reason: There is no user table or view with this name | |
END | |
END | |
--Variable declarations | |
DECLARE @Column_ID int, | |
@Column_List varchar(8000), | |
@Column_List_For_Update varchar(8000), | |
@Column_List_For_Check varchar(8000), | |
@Column_Name varchar(128), | |
@Column_Name_Unquoted varchar(128), | |
@Data_Type varchar(128), | |
@Actual_Values nvarchar(max), --This is the string that will be finally executed to generate a MERGE statement | |
@IDN varchar(128), --Will contain the IDENTITY column's name in the table | |
@Target_Table_For_Output varchar(776), | |
@Source_Table_Qualified varchar(776) | |
--Variable Initialization | |
SET @IDN = '' | |
SET @Column_ID = 0 | |
SET @Column_Name = '' | |
SET @Column_Name_Unquoted = '' | |
SET @Column_List = '' | |
SET @Column_List_For_Update = '' | |
SET @Column_List_For_Check = '' | |
SET @Actual_Values = '' | |
--Variable Defaults | |
IF @schema IS NULL | |
BEGIN | |
SET @Target_Table_For_Output = QUOTENAME(COALESCE(@target_table, @table_name)) | |
END | |
ELSE | |
BEGIN | |
SET @Target_Table_For_Output = QUOTENAME(@schema) + '.' + QUOTENAME(COALESCE(@target_table, @table_name)) | |
END | |
SET @Source_Table_Qualified = QUOTENAME(COALESCE(@schema,SCHEMA_NAME())) + '.' + QUOTENAME(@table_name) | |
--To get the first column's ID | |
SELECT @Column_ID = MIN(ORDINAL_POSITION) | |
FROM INFORMATION_SCHEMA.COLUMNS (NOLOCK) | |
WHERE TABLE_NAME = @table_name | |
AND TABLE_SCHEMA = COALESCE(@schema, SCHEMA_NAME()) | |
--Loop through all the columns of the table, to get the column names and their data types | |
WHILE @Column_ID IS NOT NULL | |
BEGIN | |
SELECT @Column_Name = QUOTENAME(COLUMN_NAME), | |
@Column_Name_Unquoted = COLUMN_NAME, | |
@Data_Type = DATA_TYPE | |
FROM INFORMATION_SCHEMA.COLUMNS (NOLOCK) | |
WHERE ORDINAL_POSITION = @Column_ID | |
AND TABLE_NAME = @table_name | |
AND TABLE_SCHEMA = COALESCE(@schema, SCHEMA_NAME()) | |
IF @cols_to_include IS NOT NULL --Selecting only user specified columns | |
BEGIN | |
IF CHARINDEX( '''' + SUBSTRING(@Column_Name,2,LEN(@Column_Name)-2) + '''',@cols_to_include) = 0 | |
BEGIN | |
GOTO SKIP_LOOP | |
END | |
END | |
IF @cols_to_exclude IS NOT NULL --Selecting only user specified columns | |
BEGIN | |
IF CHARINDEX( '''' + SUBSTRING(@Column_Name,2,LEN(@Column_Name)-2) + '''',@cols_to_exclude) <> 0 | |
BEGIN | |
GOTO SKIP_LOOP | |
END | |
END | |
--Making sure to output SET IDENTITY_INSERT ON/OFF in case the table has an IDENTITY column | |
IF (SELECT COLUMNPROPERTY( OBJECT_ID(@Source_Table_Qualified),SUBSTRING(@Column_Name,2,LEN(@Column_Name) - 2),'IsIdentity')) = 1 | |
BEGIN | |
IF @ommit_identity = 0 --Determing whether to include or exclude the IDENTITY column | |
SET @IDN = @Column_Name | |
ELSE | |
GOTO SKIP_LOOP | |
END | |
--Making sure whether to output computed columns or not | |
IF @ommit_computed_cols = 1 | |
BEGIN | |
IF (SELECT COLUMNPROPERTY( OBJECT_ID(@Source_Table_Qualified),SUBSTRING(@Column_Name,2,LEN(@Column_Name) - 2),'IsComputed')) = 1 | |
BEGIN | |
GOTO SKIP_LOOP | |
END | |
END | |
--Tables with columns of IMAGE data type are not supported for obvious reasons | |
IF(@Data_Type in ('image')) | |
BEGIN | |
IF (@ommit_images = 0) | |
BEGIN | |
RAISERROR('Tables with image columns are not supported.',16,1) | |
PRINT 'Use @ommit_images = 1 parameter to generate a MERGE for the rest of the columns.' | |
RETURN -1 --Failure. Reason: There is a column with image data type | |
END | |
ELSE | |
BEGIN | |
GOTO SKIP_LOOP | |
END | |
END | |
--Determining the data type of the column and depending on the data type, the VALUES part of | |
--the MERGE statement is generated. Care is taken to handle columns with NULL values. Also | |
--making sure, not to lose any data from flot, real, money, smallmomey, datetime columns | |
SET @Actual_Values = @Actual_Values + | |
CASE | |
WHEN @Data_Type IN ('char','nchar') | |
THEN | |
'COALESCE(''N'''''' + REPLACE(RTRIM(' + @Column_Name + '),'''''''','''''''''''')+'''''''',''NULL'')' | |
WHEN @Data_Type IN ('varchar','nvarchar') | |
THEN | |
'COALESCE(''N'''''' + REPLACE(' + @Column_Name + ','''''''','''''''''''')+'''''''',''NULL'')' | |
WHEN @Data_Type IN ('datetime','smalldatetime','datetime2','date','datetimeoffset','time') | |
THEN | |
'COALESCE('''''''' + RTRIM(CONVERT(char,' + @Column_Name + ',127))+'''''''',''NULL'')' | |
WHEN @Data_Type IN ('uniqueidentifier') | |
THEN | |
'COALESCE(''N'''''' + REPLACE(CONVERT(char(36),RTRIM(' + @Column_Name + ')),'''''''','''''''''''')+'''''''',''NULL'')' | |
WHEN @Data_Type IN ('text') | |
THEN | |
'COALESCE(''N'''''' + REPLACE(CONVERT(varchar(max),' + @Column_Name + '),'''''''','''''''''''')+'''''''',''NULL'')' | |
WHEN @Data_Type IN ('ntext') | |
THEN | |
'COALESCE('''''''' + REPLACE(CONVERT(nvarchar(max),' + @Column_Name + '),'''''''','''''''''''')+'''''''',''NULL'')' | |
WHEN @Data_Type IN ('xml') | |
THEN | |
'COALESCE('''''''' + REPLACE(CONVERT(nvarchar(max),' + @Column_Name + '),'''''''','''''''''''')+'''''''',''NULL'')' | |
WHEN @Data_Type IN ('binary','varbinary') | |
THEN | |
'COALESCE(RTRIM(CONVERT(varchar(max),' + @Column_Name + ', 1)),''NULL'')' | |
WHEN @Data_Type IN ('timestamp','rowversion') | |
THEN | |
CASE | |
WHEN @include_timestamp = 0 | |
THEN | |
'''DEFAULT''' | |
ELSE | |
'COALESCE(RTRIM(CONVERT(char,' + 'CONVERT(int,' + @Column_Name + '))),''NULL'')' | |
END | |
WHEN @Data_Type IN ('float','real','money','smallmoney') | |
THEN | |
'COALESCE(LTRIM(RTRIM(' + 'CONVERT(char, ' + @Column_Name + ',2)' + ')),''NULL'')' | |
WHEN @Data_Type IN ('hierarchyid') | |
THEN | |
'COALESCE(''hierarchyid::Parse(''+'''''''' + LTRIM(RTRIM(' + 'CONVERT(char, ' + @Column_Name + ')' + '))+''''''''+'')'',''NULL'')' | |
ELSE | |
'COALESCE(LTRIM(RTRIM(' + 'CONVERT(char, ' + @Column_Name + ')' + ')),''NULL'')' | |
END + '+' + ''',''' + ' + ' | |
--Generating the column list for the MERGE statement | |
SET @Column_List = @Column_List + @Column_Name + ',' | |
--Don't update Primary Key or Identity columns | |
IF NOT EXISTS( | |
SELECT 1 | |
FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS pk , | |
INFORMATION_SCHEMA.KEY_COLUMN_USAGE c | |
WHERE pk.TABLE_NAME = @table_name | |
AND pk.TABLE_SCHEMA = COALESCE(@schema, SCHEMA_NAME()) | |
AND CONSTRAINT_TYPE = 'PRIMARY KEY' | |
AND c.TABLE_NAME = pk.TABLE_NAME | |
AND c.TABLE_SCHEMA = pk.TABLE_SCHEMA | |
AND c.CONSTRAINT_NAME = pk.CONSTRAINT_NAME | |
AND c.COLUMN_NAME = @Column_Name_Unquoted | |
) | |
BEGIN | |
SET @Column_List_For_Update = @Column_List_For_Update + @Column_Name + ' = Source.' + @Column_Name + ', | |
' | |
SET @Column_List_For_Check = @Column_List_For_Check + | |
CASE @Data_Type | |
WHEN 'text' THEN CHAR(10) + CHAR(9) + 'NULLIF(CAST(Source.' + @Column_Name + ' AS VARCHAR(MAX)), CAST(Target.' + @Column_Name + ' AS VARCHAR(MAX))) IS NOT NULL OR NULLIF(CAST(Target.' + @Column_Name + ' AS VARCHAR(MAX)), CAST(Source.' + @Column_Name + ' AS VARCHAR(MAX))) IS NOT NULL OR ' | |
WHEN 'ntext' THEN CHAR(10) + CHAR(9) + 'NULLIF(CAST(Source.' + @Column_Name + ' AS NVARCHAR(MAX)), CAST(Target.' + @Column_Name + ' AS NVARCHAR(MAX))) IS NOT NULL OR NULLIF(CAST(Target.' + @Column_Name + ' AS NVARCHAR(MAX)), CAST(Source.' + @Column_Name + ' AS NVARCHAR(MAX))) IS NOT NULL OR ' | |
ELSE CHAR(10) + CHAR(9) + 'NULLIF(Source.' + @Column_Name + ', Target.' + @Column_Name + ') IS NOT NULL OR NULLIF(Target.' + @Column_Name + ', Source.' + @Column_Name + ') IS NOT NULL OR ' | |
END | |
END | |
SKIP_LOOP: --The label used in GOTO | |
SELECT @Column_ID = MIN(ORDINAL_POSITION) | |
FROM INFORMATION_SCHEMA.COLUMNS (NOLOCK) | |
WHERE TABLE_NAME = @table_name | |
AND TABLE_SCHEMA = COALESCE(@schema, SCHEMA_NAME()) | |
AND ORDINAL_POSITION > @Column_ID | |
END --Loop ends here! | |
--To get rid of the extra characters that got concatenated during the last run through the loop | |
IF LEN(@Column_List_For_Update) <> 0 | |
BEGIN | |
SET @Column_List_For_Update = ' ' + LEFT(@Column_List_For_Update,len(@Column_List_For_Update) - 4) | |
END | |
IF LEN(@Column_List_For_Check) <> 0 | |
BEGIN | |
SET @Column_List_For_Check = LEFT(@Column_List_For_Check,len(@Column_List_For_Check) - 3) | |
END | |
SET @Actual_Values = LEFT(@Actual_Values,len(@Actual_Values) - 6) | |
SET @Column_List = LEFT(@Column_List,len(@Column_List) - 1) | |
IF LEN(LTRIM(@Column_List)) = 0 | |
BEGIN | |
RAISERROR('No columns to select. There should at least be one column to generate the output',16,1) | |
RETURN -1 --Failure. Reason: Looks like all the columns are ommitted using the @cols_to_exclude parameter | |
END | |
--Get the join columns ---------------------------------------------------------- | |
DECLARE @PK_column_list VARCHAR(8000) | |
DECLARE @PK_column_joins VARCHAR(8000) | |
SET @PK_column_list = '' | |
SET @PK_column_joins = '' | |
SELECT @PK_column_list = @PK_column_list + '[' + c.COLUMN_NAME + '], ' | |
, @PK_column_joins = @PK_column_joins + 'Target.[' + c.COLUMN_NAME + '] = Source.[' + c.COLUMN_NAME + '] AND ' | |
FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS pk , | |
INFORMATION_SCHEMA.KEY_COLUMN_USAGE c | |
WHERE pk.TABLE_NAME = @table_name | |
AND pk.TABLE_SCHEMA = COALESCE(@schema, SCHEMA_NAME()) | |
AND CONSTRAINT_TYPE = 'PRIMARY KEY' | |
AND c.TABLE_NAME = pk.TABLE_NAME | |
AND c.TABLE_SCHEMA = pk.TABLE_SCHEMA | |
AND c.CONSTRAINT_NAME = pk.CONSTRAINT_NAME | |
IF IsNull(@PK_column_list, '') = '' | |
BEGIN | |
RAISERROR('Table has no primary keys. There should at least be one column in order to have a valid join.',16,1) | |
RETURN -1 --Failure. Reason: looks like table doesn't have any primary keys | |
END | |
SET @PK_column_list = LEFT(@PK_column_list, LEN(@PK_column_list) -1) | |
SET @PK_column_joins = LEFT(@PK_column_joins, LEN(@PK_column_joins) -4) | |
--Forming the final string that will be executed, to output the a MERGE statement | |
SET @Actual_Values = | |
'SELECT ' + | |
CASE WHEN @top IS NULL OR @top < 0 THEN '' ELSE ' TOP ' + LTRIM(STR(@top)) + ' ' END + | |
'''' + | |
' '' + CASE WHEN ROW_NUMBER() OVER (ORDER BY ' + @PK_column_list + ') = 1 THEN '' '' ELSE '','' END + ''(''+ ' + @Actual_Values + '+'')''' + ' ' + | |
COALESCE(@from,' FROM ' + @Source_Table_Qualified + ' (NOLOCK) ORDER BY ' + @PK_column_list) | |
DECLARE @output VARCHAR(MAX) = '' | |
DECLARE @b CHAR(1) = CHAR(13) | |
--Determining whether to ouput any debug information | |
IF @debug_mode =1 | |
BEGIN | |
SET @output += @b + '/*****START OF DEBUG INFORMATION*****' | |
SET @output += @b + '' | |
SET @output += @b + 'The primary key column list:' | |
SET @output += @b + @PK_column_list | |
SET @output += @b + '' | |
SET @output += @b + 'The INSERT column list:' | |
SET @output += @b + @Column_List | |
SET @output += @b + '' | |
SET @output += @b + 'The UPDATE column list:' | |
SET @output += @b + @Column_List_For_Update | |
SET @output += @b + '' | |
SET @output += @b + 'The SELECT statement executed to generate the MERGE:' | |
SET @output += @b + @Actual_Values | |
SET @output += @b + '' | |
SET @output += @b + '*****END OF DEBUG INFORMATION*****/' | |
SET @output += @b + '' | |
END | |
IF (@include_use_db = 1) | |
BEGIN | |
SET @output += 'USE ' + DB_NAME() | |
SET @output += @b + @batch_separator | |
SET @output += @b + @b | |
END | |
IF (@nologo = 0) | |
BEGIN | |
SET @output += @b + '--MERGE generated by ''sp_generate_merge'' stored procedure, Version 0.93' | |
SET @output += @b + '--Originally by Vyas (http://vyaskn.tripod.com): sp_generate_inserts (build 22)' | |
SET @output += @b + '--Adapted for SQL Server 2008/2012 by Daniel Nolan (http://danere.com)' | |
SET @output += @b + '' | |
END | |
IF (@include_rowsaffected = 1) -- If the caller has elected not to include the "rows affected" section, let MERGE output the row count as it is executed. | |
SET @output += @b + 'SET NOCOUNT ON' | |
SET @output += @b + '' | |
--Determining whether to print IDENTITY_INSERT or not | |
IF (LEN(@IDN) <> 0) | |
BEGIN | |
SET @output += @b + 'SET IDENTITY_INSERT ' + @Target_Table_For_Output + ' ON' | |
SET @output += @b + '' | |
END | |
--Temporarily disable constraints on the target table | |
IF @disable_constraints = 1 AND (OBJECT_ID(@Source_Table_Qualified, 'U') IS NOT NULL) | |
BEGIN | |
SET @output += @b + 'ALTER TABLE ' + @Target_Table_For_Output + ' NOCHECK CONSTRAINT ALL' --Code to disable constraints temporarily | |
END | |
--Output the start of the MERGE statement, qualifying with the schema name only if the caller explicitly specified it | |
SET @output += @b + 'MERGE INTO ' + @Target_Table_For_Output + ' AS Target' | |
SET @output += @b + 'USING (VALUES' | |
--All the hard work pays off here!!! You'll get your MERGE statement, when the next line executes! | |
DECLARE @tab TABLE (ID INT NOT NULL PRIMARY KEY IDENTITY(1,1), val NVARCHAR(max)); | |
INSERT INTO @tab (val) | |
EXEC (@Actual_Values) | |
IF (SELECT COUNT(*) FROM @tab) <> 0 -- Ensure that rows were returned, otherwise the MERGE statement will get nullified. | |
BEGIN | |
SET @output += CAST((SELECT @b + val FROM @tab ORDER BY ID FOR XML PATH('')) AS XML).value('.', 'VARCHAR(MAX)'); | |
END | |
--Output the columns to correspond with each of the values above-------------------- | |
SET @output += @b + ') AS Source (' + @Column_List + ')' | |
--Output the join columns ---------------------------------------------------------- | |
SET @output += @b + 'ON (' + @PK_column_joins + ')' | |
--When matched, perform an UPDATE on any metadata columns only (ie. not on PK)------ | |
IF LEN(@Column_List_For_Update) <> 0 | |
BEGIN | |
SET @output += @b + 'WHEN MATCHED ' + CASE WHEN @update_only_if_changed = 1 THEN 'AND (' + @Column_List_For_Check + ') ' ELSE '' END + 'THEN' | |
SET @output += @b + ' UPDATE SET' | |
SET @output += @b + ' ' + LTRIM(@Column_List_For_Update) | |
END | |
--When NOT matched by target, perform an INSERT------------------------------------ | |
SET @output += @b + 'WHEN NOT MATCHED BY TARGET THEN'; | |
SET @output += @b + ' INSERT(' + @Column_List + ')' | |
SET @output += @b + ' VALUES(' + REPLACE(@Column_List, '[', 'Source.[') + ')' | |
--When NOT matched by source, DELETE the row | |
IF @delete_if_not_matched=1 BEGIN | |
SET @output += @b + 'WHEN NOT MATCHED BY SOURCE THEN ' | |
SET @output += @b + ' DELETE' | |
END; | |
SET @output += @b + ';' | |
SET @output += @b + @batch_separator | |
--Display the number of affected rows to the user, or report if an error occurred--- | |
IF @include_rowsaffected = 1 | |
BEGIN | |
SET @output += @b + 'DECLARE @mergeError int' | |
SET @output += @b + ' , @mergeCount int' | |
SET @output += @b + 'SELECT @mergeError = @@ERROR, @mergeCount = @@ROWCOUNT' | |
SET @output += @b + 'IF @mergeError != 0' | |
SET @output += @b + ' BEGIN' | |
SET @output += @b + ' PRINT ''ERROR OCCURRED IN MERGE FOR ' + @Target_Table_For_Output + '. Rows affected: '' + CAST(@mergeCount AS VARCHAR(100)); -- SQL should always return zero rows affected'; | |
SET @output += @b + ' END' | |
SET @output += @b + 'ELSE' | |
SET @output += @b + ' BEGIN' | |
SET @output += @b + ' PRINT ''' + @Target_Table_For_Output + ' rows affected by MERGE: '' + CAST(@mergeCount AS VARCHAR(100));'; | |
SET @output += @b + ' END' | |
SET @output += @b + @batch_separator | |
SET @output += @b + @b | |
END | |
--Re-enable the previously disabled constraints------------------------------------- | |
IF @disable_constraints = 1 AND (OBJECT_ID(@Source_Table_Qualified, 'U') IS NOT NULL) | |
BEGIN | |
SET @output += 'ALTER TABLE ' + @Target_Table_For_Output + ' CHECK CONSTRAINT ALL' --Code to enable the previously disabled constraints | |
SET @output += @b + @batch_separator | |
SET @output += @b | |
END | |
--Switch-off identity inserting------------------------------------------------------ | |
IF (LEN(@IDN) <> 0) | |
BEGIN | |
SET @output += 'SET IDENTITY_INSERT ' + @Target_Table_For_Output + ' OFF' | |
SET @output += @b + @batch_separator | |
SET @output += @b | |
END | |
IF (@include_rowsaffected = 1) | |
BEGIN | |
SET @output += 'SET NOCOUNT OFF' | |
SET @output += @b + @batch_separator | |
SET @output += @b | |
END | |
SET @output += @b + '' | |
SET @output += @b + '' | |
IF @results_to_text = 1 | |
BEGIN | |
--output the statement to the Grid/Messages tab | |
SELECT @output; | |
END | |
ELSE | |
BEGIN | |
--output the statement as xml (to overcome SSMS 4000/8000 char limitation) | |
SELECT [processing-instruction(x)]=@output FOR XML PATH(''),TYPE; | |
PRINT 'MERGE statement has been wrapped in an XML fragment and output successfully.' | |
PRINT 'Ensure you have Results to Grid enabled and then click the hyperlink to copy the statement within the fragment.' | |
PRINT '' | |
PRINT 'If you would prefer to have results output directly (without XML) specify @results_to_text = 1, however please' | |
PRINT 'note that the results may be truncated by your SQL client to 4000 nchars.' | |
END | |
SET NOCOUNT OFF | |
RETURN 0 --Success. We are done! | |
END | |
GO |
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