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ecpg(1) [centos man page]

ECPG(1) 						  PostgreSQL 9.2.7 Documentation						   ECPG(1)

ecpg - embedded SQL C preprocessor SYNOPSIS
ecpg [option...] file... DESCRIPTION
ecpg is the embedded SQL preprocessor for C programs. It converts C programs with embedded SQL statements to normal C code by replacing the SQL invocations with special function calls. The output files can then be processed with any C compiler tool chain. ecpg will convert each input file given on the command line to the corresponding C output file. Input files preferably have the extension .pgc, in which case the extension will be replaced by .c to determine the output file name. If the extension of the input file is not .pgc, then the output file name is computed by appending .c to the full file name. The output file name can also be overridden using the -o option. This reference page does not describe the embedded SQL language. See Chapter 33, ECPG - Embedded SQL in C, in the documentation for more information on that topic. OPTIONS
ecpg accepts the following command-line arguments: -c Automatically generate certain C code from SQL code. Currently, this works for EXEC SQL TYPE. -C mode Set a compatibility mode. mode can be INFORMIX or INFORMIX_SE. -D symbol Define a C preprocessor symbol. -h Parse a header file, this option includes otion -c. -i Parse system include files as well. -I directory Specify an additional include path, used to find files included via EXEC SQL INCLUDE. Defaults are . (current directory), /usr/local/include, the PostgreSQL include directory which is defined at compile time (default: /usr/local/pgsql/include), and /usr/include, in that order. -o filename Specifies that ecpg should write all its output to the given filename. -r option Selects run-time behavior. Option can be one of the following: no_indicator Do not use indicators but instead use special values to represent null values. Historically there have been databases using this approach. prepare Prepare all statements before using them. Libecpg will keep a cache of prepared statements and reuse a statement if it gets executed again. If the cache runs full, libecpg will free the least used statement. questionmarks Allow question mark as placeholder for compatibility reasons. This used to be the default long ago. --regression Run in regression testing mode. -t Turn on autocommit of transactions. In this mode, each SQL command is automatically committed unless it is inside an explicit transaction block. In the default mode, commands are committed only when EXEC SQL COMMIT is issued. -v Print additional information including the version and the "include" path. --version Print the ecpg version and exit. -?, --help Show help about ecpg command line arguments, and exit. NOTES
When compiling the preprocessed C code files, the compiler needs to be able to find the ECPG header files in the PostgreSQL include directory. Therefore, you might have to use the -I option when invoking the compiler (e.g., -I/usr/local/pgsql/include). Programs using C code with embedded SQL have to be linked against the libecpg library, for example using the linker options -L/usr/local/pgsql/lib -lecpg. The value of either of these directories that is appropriate for the installation can be found out using pg_config(1). EXAMPLES
If you have an embedded SQL C source file named prog1.pgc, you can create an executable program using the following sequence of commands: ecpg prog1.pgc cc -I/usr/local/pgsql/include -c prog1.c cc -o prog1 prog1.o -L/usr/local/pgsql/lib -lecpg PostgreSQL 9.2.7 2014-02-17 ECPG(1)

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SELECT INTO - create a new table from the results of a query SYNOPSIS
SELECT [ ALL | DISTINCT [ ON ( expression [, ...] ) ] ] * | expression [ AS output_name ] [, ...] INTO [ TEMPORARY | TEMP ] [ TABLE ] new_table [ FROM from_item [, ...] ] [ WHERE condition ] [ GROUP BY expression [, ...] ] [ HAVING condition [, ...] ] [ { UNION | INTERSECT | EXCEPT } [ ALL ] select ] [ ORDER BY expression [ ASC | DESC | USING operator ] [, ...] ] [ LIMIT { count | ALL } ] [ OFFSET start ] [ FOR UPDATE [ OF tablename [, ...] ] ] INPUTS TEMPORARY TEMP If specified, the table is created as a temporary table. Refer to CREATE TABLE [create_table(7)] for details. new_table The name (optionally schema-qualified) of the table to be created. All other inputs are described in detail for SELECT [select(7)]. OUTPUTS Refer to CREATE TABLE [create_table(7)] and SELECT [select(7)] for a summary of possible output messages. DESCRIPTION
SELECT INTO creates a new table and fills it with data computed by a query. The data is not returned to the client, as it is with a normal SELECT. The new table's columns have the names and data types associated with the output columns of the SELECT. Note: CREATE TABLE AS [create_table_as(7)] is functionally equivalent to SELECT INTO. CREATE TABLE AS is the recommended syntax, since SELECT INTO is not standard. In fact, this form of SELECT INTO is not available in PL/pgSQL or ecpg(1), because they interpret the INTO clause differently. COMPATIBILITY
SQL92 uses SELECT ... INTO to represent selecting values into scalar variables of a host program, rather than creating a new table. This indeed is the usage found in PL/pgSQL and ecpg(1). The PostgreSQL usage of SELECT INTO to represent table creation is historical. It's best to use CREATE TABLE AS for this purpose in new code. (CREATE TABLE AS isn't standard either, but it's less likely to cause confu- sion.) SQL - Language Statements 2002-11-22 SELECT INTO(7)
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